So has anybody been able to find a datasheet for the 5530? There seem to be lots of them available, just not in small quantities or low minimum orders. The only summary I could find said it's a 3MHz dual with 150nA input current. In any normal app I wouldn't hesitate to sub it with any of the parts listed in the above post, but as part of a power amp, I'd be more cautious. A part with "better" specs might not be stable. Or it might work better than it ever worked before. You'd want to check for oscillations and such.

" " Match , Like No Data, NE5532(4) NE5533(1) NE5534(5) NE5535(1) NE5537(1) NE5539(2) ..." From http://www.alldatasheet.com/view.jsp?Searchword=NE5530D ... that's what you get from a googler search for '5530 = no match / no data = ... although there may be something out there, I don't usually read the second page search results ... bad habit, but ...

Originally posted by javey I was replying to gold and others. QSC said 5530 was obsolete(and they are unless you order from the $300 minimum warehouses) and told me 5532's would not work. They did not make any suggestions as to what would,simply saying save yourself the hassle and buy a PLX.

I just can't see how they can say 5532 won't work. It's unity gain stable and has good power capabilities. You have confirmed the 5530 is a dual device, so all that's left really is the pinout. Maybe they were being lazy/arrogant and just want a new sale.

The only other possibility is that 5530 is a transconductance amplifier. Unlikely though. I say drop a 5532 in and see what happens.

This is the unedited response cut and pasted from QSC's Thanh Nguyen who I also asked about what were the stock OT's and drivers.
"If itís not in good condition, I suggest buying a new RMX850 instead of restoring this amplifier. QSC Technical Services no longer service the A-Series amplifiers since they were discontinued in the early 1980s.
Note that ECG130/219 were not QSC parts; Op-amp NE5532 would not work properly in A32 circuitry and NE5530 is obsolete."

Thanks Eddie for all the info! I'll let you guys know as soon as I get my hands on these and throw them in.

OF special interest here: The QSC 1400 uses the afore mentioned NE5532 and the first amplification stage ... ... and that's basically why I have junked one of the amps, saving the chassis & PS for a "better" amp board ( aussieamplifiers.com ... the NX500NL times two).

Also your english is quite passable ... no need to appologize for it at all. (Mine is not that great ... )